Detergent compositions

ABSTRACT

A liquid detergent system having a controllable viscosity and clarity, including a water-soluble paraffin sulfonate and a water-soluble, higher alkane, ether sulfate. Control of the viscosity and clarity is accomplished by using a control system comprising a lower aliphatic alcohol and urea.

United States Patent [191 Verdier DETERGENT COMPOSITIONS [75] Inventor:Denise Verdler, Le Bourget, France v [73] Assignee: Colgate-PalmoliveCompany, New

York, NY.

[22] Filed: Feb. 25, 1971 [21] Appl. No.: 118,939

[30] Foreign Application Priority Data Mar. 9, 1970 France 7008310 Nov.9, 1970 France 7040196 [52] US. Cl 252/545, 252/548, 252/551,

252/552, 252/153 [51] Int. Cl.....C1ld 1/14, Cl1d1/37, C1ld1/655,

1 1 Aug. 28, 1973 3,231,504 1/1966 Marion et a1, 252/551 X 2,941,9506/1960 Korpi et a1 252/551 X 3,308,068 3/1967 Jones 252/554 FOREIGNPATENTS OR APPLICATIONS 1,104,692 2/1968 Great Britain 279,352 1/ 1965Australia 513,726 9/1952 Belgium 214,861 5/1958 Australia 808,805 2/1959Great Britain Primary Examiner-Leon D. Rosdol Assistant ExaminerP. E.Willis Attorney-I-Ierbert S. Sylvester, Murray M. Grill, NormanBlumenkopf, Ronald S. Cornell, Thomas J. Corum, Richard N. Miller andRobert L. Stone [57] ABSTRACT A liquid detergent system having acontrollable viscosity and clarity, including a water-soluble paraffinsulfonate and a water-soluble, higher alkane, ether sulfate. Control ofthe viscosity and clarity is accomplished by using a control systemcomprising a lower aliphatic a1- cohol and urea.

9 Claims, No Drawings DETERGENT COMPOSITIONS The present inventionrelates to clear, stable, liquid detergent compositions containing:

A. Water soluble salts of paraffin sulfonates,

B. Compatible water soluble salts of higher alkyl ether sulfates in aratio of A:B of about :1 to 1:1, and

C. a viscosity and clarity control system. Preferably, the compositionsare prepared in the form of a clear, stable liquid detergent compositioncontain ing A and B in a total content of about 10 to about 60 percentby weight in an aqueous medium.

Liquid detergent compositions are known which comprise sodium dodecylbenzene sulfonate and ammonium alkyl ether sulfate. In order toformulate liquid detergents comprising these two ingredients insufficient concentration to be practical, it has been necessary toinclude in the composition relatively high proportions of solubilizingagents or hydrotropes such as the lower aliphatic alcohols (e.g., ethylalcohol), urea,

low molecular weight alkylbenzene sulfonates (e.g., sodium xylenesulfonate), and the like.

It has now been discovered that commercially acceptable liquid detergentcompositions can be formulated based on:

A. water soluble salts of paraffin sulfonates,

B. compatible water soluble salts of alkyl ether sulfates, ashereinafter defined, with as high as 60 percent active ingredients in anaqueous liquid provided the ratio of A:B is from 10:1 to 1:1, and

C. a viscosity and clarity control system, as hereafter defined. Theliquid detergent compositions of the present invention have significantadvantages over the previously known liquid detergents based on alkylaryl sulfonates and alkyl ether sulfates.

Among the advantages of the present invention over the previously knownliquid detergents are the following:

1. Liquid detergent compositions of substantially equal percentage ofactive ingredients and comparable clarity can be produced in accordancewith the present invention with significantly lower percentages ofhydrotropes than were necessarily used in-the previously knowncompositions.

2. The compositions of the present invention produce better foam thanthe prior art compositions both in quantity and durability.

3. Compositions of the present invention,when diluted to the sameconcentration for use as the prior art compositions give substantiallyhigher performance, particularly in dish washing.

4. Washing compositions made with the product of the present inventionalso have significantly lower surface tension than compositions of thesame concentration using prior art compositions.

Among the advantages of the present invention are improved andcontrolled performance such as foaming and dish washing ability,viscosity and clarity which are important features in consumeracceptability.

The paraffin sulfonates used in the present invention are usually mixedsecondary alkyl sulfonates having from ten to twenty carbon atoms permolecule, preferably they will have at least 80 percent, usually atleast 90 percent, of from 10-17 carbon atoms per molecule. Where themajor proportion has 14-15 carbon atoms per molecule, optimum foamingperformance appears to be obtained at varying concentrations and waterhardnesses. These sulfonates are preferably prepared by subjecting a cutof paraffin, corresponding to the chain lengths specified above, to theaction of sulfur dioxide and oxygen in accordance with the well knownsulfoxidation process. The product of this reaction is a secondarysulfonic acid which is then neutralized with a suitable base to providethe water soluble secondary alkyl sulfonate for use in the presentinvention. Similar useful secondary alkyl sulfonates may be obtained byother methods, e.g., by the sulfochlorination method in which chlorineand sulfur dioxide are reacted with paraffins in the presence of actiniclight, the resulting sulforyl chlorides being hydrolyzed and neutralizedto form the secondary alkyl sulfonates.

The higher alkyl ether sulfates used in the present invention arerepresented by the formula:

in which R is a primary or secondary alkyl group that may be straight orbranched having from 10 to 18 carbon atoms, preferably 12 to 14, X is asuitable cation, as hereinafter defined, and n is a number from 1 to 10,preferably 3' to 6. These detergents are produced by sulfating thecorresponding ether alcohol and then neutralizing the resulting sulfuricacid ester thereof.

The cation of the paraffin sulfonate and alkyl ether sulfate may be analkali metal, an alkaline earth metal (e.g., magnesium), ammonium orlower amine (including alkylolamines). It is preferred to use the sodiumsalt of the paraffin sulfonic acid and an ammonium salt of the alkylether sulfuric acid ester.

It is advantageous to include non-ionic surface active agents in thecomposition to improve the quantity and the lasting quality of the foam.Among the non-ionic surface active agents which 'may be usedsatisfactorily are higher alcohols, ether alcohols, ethoxylated phenols,and higher fatty acid amides.

It is preferred that the liquid detergent composition contain a higherfatty acid alkylolamide material in sufficient amount to act as a sudsbuilder. Its presence results in a product which exhibits high foamingpower in use, particularly in the stability of the foam generated duringdish washing or laundering operations. It should not be employed in anamount sufficient to destroy the desired physical properties. The acylradical of the alkylolamide is selected from the class of fatty acidshaving 8 to 18 carbon atoms and each alkylol group usually has up to 3-carbon atoms. It is preferred to use the monoethanolamides of lauric andmyristic acids but diethanolamides and isopropanolamides as well asmonoethanolamides of fatty acids having about 10 to 14 carbon atoms inthe acyl radical are satisfactory. Examples are capric,lauric, myristicand coconut monoethanolamides, diethanolamides and isopropanolamides andmixtures thereof. There may be employed also the alkylolamides which aresubstituted by additional alkylol groups, suitable examples may be theabove amides condensed with 1 or 2 moles of ethylene oxide.

While any suitable ratio of parafiin sulfonates to alkyl ether sulfatesmay be used as described, it has been found that the ratio should be atleast about 60 40 for an optimum combination of properties, particularlyin the presence of amide or the like. Suitable ratios are 60:40, :30,:20 and :15 by weight with 0-8 percent alkylolamide, preferably 1-6percent and usually 4-6 percent, such as coconut monoethanolamide,diethanolamide, or ethanolamide condensed with about 1-4 moles ofethylene oxide. It is understood that the sulfonate and sulfate saltsmay be in any suitable watersoluble salt form such as the sodium,potassium, ammonium, and mono-, diand tri-ethanolamine salts, or

mixtures thereof.

The higher alcohols and ether alcohols which may be used as foambuilders in the present invention are represented by the formula:

R represents an alkyl group that may be straight or branched having from10 to 18 carbon atoms and n is a number from to 10, preferably 3 to 6.1n the case of higher ether alcohols, the preferred chain length for thealkyl group is from C C when n has a value from 3-6 as preferred.

When used, the non-ionics may be present in the formula up to aboutpercent by weight of the product, preferably up to about 4 percent ofthe alcohol ether and up to about 8 percent of the fatty acidalkylolamide.

The viscosity and clarity control system used in the liquid detergentcomposition of the invention comprises urea, a lower aliphatic alcohol,and optionally a water-soluble hydrotropic substance which is effectivein promoting the compatibility of the ingredients in the liquid productand can be substituted for part of the urea or alcohol.

Suitable hydrotropic substances are the alkali metal organic sulfonated(including sulfated) salts having a lower alkyl group up to about 6carbon atoms. The preferred sulfonated hydrotropes are alkyl arylsulfonates having up to 3 carbon atoms in the lower alkyl group, e.g.,the sodium and potassium xylene, toluene, ethylbenzene and isopropylbenzene (cu mene) sulfonates. Sulfonates made from xylene includeorthoxylene sulfonate, metaxylene sulfonate, paraxylene sulfonate andethylbenzene sulfonate. Commercial xylene sulfonates usually containmetaxylene sulfonate as the main ingredient. Analysis of typicalcommercial xylene sulfonate products shows about 40-50 percentmetaxylene sulfonate, 10-35 percent orthoxylene sulfonate and -30percent paraxylene sulfonate with 0-20 percent ethylbenzene sulfonate.Any suitable isomeric mixture, however, may be employed. Sodium cumenesulfonate and sodium xylene sulfonate are preferred lower alkyl arylsulfonates to use in the compositions of the present invention. it isalso permissible to use suitably lower alkyl sulfate salts having about5 to 6 carbon atoms in the alkyl group such as alkali metal n-amyl andn-hexyl sulhol, isopropyl alcohol or propylene glycol can be used,preferably, ethyl alcohol will be used.

The exact proportions of urea, lower alcohol, and hydrotropic substancebest suited for any particular composition may be determined by theformulator by conventional tests. The weight content of this viscosityand control system based upon the total composition will vary from 25-15percent and preferably from 6 to 13 percent. Within that range, the ureaand the alcohol will vary within the ranges of 0.5 to 5.0 percent,preferably l to 4 percent and 2 to lOfpercent, preferably 5 to 8percent, respectively. It is desirable to maintain the ratio of urea toalcohol within the range of 1:15 to 1:3 parts by weight, mostpreferably, at about 122.5 when using an active ingredient content aboveabout 30 percent by weight, preferably 35-45 percent includingalkylolamide or the like. Varying amounts of hydrotrope such as xylenesulfonate or the like may be added or substituted in part for thealcohol or urea so as to form a ternary system with special propertiessuch as to markedly increase the viscosity to greater levels. The amountshould be selected by formulation so as to maintain a satisfactoryviscosity and cloud point and maintain other desirable properties.Generally, the hydrotrope may constitute up to about 50 percent byweight of the total viscosity and control system.

The liquid detergents of the present invention may also contain any ofthe additives heretofore used in other liquid detergent compositionssuch as sequestrants, e.g., salts of ethylenediamine tetraacetic acid,such as the sodium and potassium salts, and salts of hydroxy ethylethylene diamine triacetate. It is desirable in some cases to tint orcolor the liquid detergent composition and any suitable dyes may be usedfor this purpose. Perfume may also be added to these compositions togive them a pleasant odor.

Water is used as the liquid vehicle for the liquid detergentcompositions of the present invention. It will vary in proportion fromabout 50 to percent, depending upon the content of the other ingredientsof the composition.

In order to illustrate some of the benefits of the present invention,two compositions containing sulfonated hydrotropes and alcohol arecompared with two conventional type liquid detergent compositions basedon sodium dodecyl benzene sulfonate. Table 1 sets forth the fourcompositions. Sodium paraffin sulfonate is used in Examples 1 and 2 atthe same level of concentration as the sodium dodecyl benzene sulfonateis used in Examples 1A and 2A respectively. Ammonium alkyl ether sulfateis also present at the same levels in each Example of pair 1 and 1A andof pair 2 and 2A. The non-ionic detergent (alcohol ether in Examples 1and 1A and lauric myristic monoethanol amide in Examples 2 and 2A) isalso at the same level in the two Examples of each pair. The sodiumxylene sulfonate and alcohol content is adjusted to give the samephysical properties to each Example of pair 1 and 1A and of pair 2 and2A, respectively. The import of Table l is that satisfactory formulashaving properties quite comparable from the physical standpoint withprior art formulas are obtainable in accordance with the presentinvention with a significantly reduced percentage of alcohol and sodiumxylene sulfonate.

TABLE I Example SPS SDBS AMAES AE LMMEA SXS l ETHOH 1 11 Sodium paraffinsulfonate O a-C1 Sodium dodecylbenzene sulfonate.

alcohol.

* Alcohol ether, C12'C15, with 3 moles of ethylene oxide per mole ofalcohol.

Laurie myrlstic monoethanolamide. Commercial sodium xylene sulfonate. aEthyl alcohol.

Referring to Table I, it will be noted in Example 1 that the samephysical properties were obtained with 6 percent ethyl alcohol thatrequired 8.5 percent for Example lA. Example 2 had the same physicalproperties with 4 percent sodium xylene sulfonate and 5.5 percentalcohol that Example 2A possessed at 6 percent sodium xylene sulfon-ateand 7 percent alcohol.

Table ll compares the results of two different performance tests onwashing solutions made from Examples l and 2 and rom Examples 1A and 2A.One of the performance tests is a dishwashing test which was carried outat two different levels of water hardness, viz., at 50 and 300 parts permillion (PPM) of hardness, and at two concentrations of detergent, viz.,0.075 percent and 0.15 percent for each level of water hardness. Theother test is a test of foam height at 300 parts per million waterhardness at 0.05 percent level of concentration of detergent.

The dishwashing tests mentioned above and hereinafter were carried outby uniformly soiling standard plates with a soil which consists of acommercial hydrogenated fatty (cottonseed) oil by spreading a smallamount, equally, on each plate.

The plates are washed in di'shpans which contain 6 liters of wash waterat 43C. Each of the compositions to be tested (at the two differentconcentrations of the liquid detergent, and at the two different waterhardnesses) is prepared and placed, separately, in different dishpans.The plates are then washed in the dishpans to an endpoint of a permanentbreak in the foam covering the dishpan; the number of plates which canbe washed to that end point is noted and recorded. A difference of 2plates in the results obtained is generally considered necessary inorder to be significant at a 95 percent confidence level.

The second test also mentioned above and which is employed to ascertainthe foam characteristics of the compositions is the foam height test,and specifically, the well known Ross & Miles Test (Pour Foam Test).This test consists essentially of measuring foam in a measuringcylinder. A jacketed measuring cylinder is employed into which a portionof the solution (at 0.05 percent in 300 ppm water) to be tested isplaced. The foam is formed by allowing a second portion of the solutionto stream in from a fixed height through a stan- Elfin Foam Number ofdishes height Water hardness-ppm.

Concentration, percent-.. 0. 075 0.15 0. 07 5 0. 0.05

Example:

dard orifice. The foam is recorded as the maximum reached in themeasuring cylinder.

It will be noted that Examples 1 and 2 are significantly better underall test conditions than Examples 1A and 2A.

The foregoing results are typical of the improved performance which canbe obtained in accordance with the present invention as compared withcompositions of the prior art.

Table III shows the improvement in surface tension of compositions ofthe present invention compared with the prior art.

TABLE III Water hardness-ppm.

Concentration, percent 0.05 0. 075 0.15 0.05 0.075 0.15

Example:

2Number of drops 151 161 137 152 I65 Zia-Number of drops 129 155 126 142TABLE IV The preferred ranges are as follows:

Parafi'm sulfonates l5-40 Alcohol ether sulfates 4-15 Alkylolamide oralkylolamide Eto condensate 0- 8 Urea 1- 4 Ethanol 5- 8 Water 08 Thefollowing examples further describethe invention, with all amounts beingby weight:

EXAMPLE 3 1: Sodium paraffin sulfonate 30 C C Fatty alcohol E0 l NHsulfate 8 Coconut fatty acid monoethanolamide 2 Urea 2 Ethyl alcohol 5.4Sodium ethylene diamine tetraacetate 0.075 Water (with small amounts ofcolor,

preservative and perfume) Total 100 The above product exhibitssatisfactory foaming and dishwashing properties combined with preferredphysi- EXAMPLE 4 A liquid detergent having similar properties as that ofExample 3 is prepared by substituting an equivalent amount of coconutmonoethanolamide condensed with about 2 moles of ethylene oxide for themonoethanolamide.

EXAMPLE 5 A satisfactory liquid detergent is prepared using the samematerials as Example 3 in the following prportions 22 percent paraffinsulfonate, 13 percent alkyl I ether sulfate, 5 percent lauric myristicmonoethanolamide, 5 percent urea and 6 percent ethanol with the balancebeing essentially water.

EXAMPLE 6 A satisfactory liquid detergent is prepared with the sameformula as Example 3 except that it contains 5.6 percent ethanol, 0.6percent sodium xylene sulfonate and 1.8 percent urea.

One of the advantages of the urea-lower alcohol control system is that achange in the physical characteristics of the composition is possible byvarying the ratio of alcohol to urea. In the specific composition ofExample 3, the ratio of alcohol to urea is 5.4 to 2 (2.711) whichresulted in the clear point below 7C. and the viscosity of 170. Bychanging the alcohol: urea ratio by increasing the alcohol content, itis possible to decrease the viscosity and raise the clear point whereasby decreasing the alcohol content the clear point can be lowered and theviscosity increased. l-lydrotropes such as sodium xylene sulfonate tendto have an effect similar to that of the alcohol, ie., increases thereofwill raise the clear point but lower the viscosity. It is important tobalance these constituents of the control system within the cited rangesto obtain the desired results. For optimum balance of clear point andviscosity, the total content of the control system will vary with thecontent of the active ingredients (paraffin sulfonate, alcohol ethersulfate and non-ionic detergents).

The clear point is also influenced by the amount of esters in the amideand sodium sulfate in the paraffin sulfonate and alkyl ether sulfateused as raw materials in preparing the compositions and, forcompositions having a low clear point, raw materials with low content ofthese impurities should be used. The characteristics given above for thespecific composition of Example 3 can best be obtained if the amide doesnot contain over 2 percent esters and the paraffin sulfonate does notcontain over 4 percent sodium sulfate.

Although the present invention has been described and illustrated withreference to certain specific compositions, these are to be consideredas illustrative of and not as limitations on the present invention. Allproportions are given hereinabove in percentages by weight of the entirecomposition unless otherwise indicated.

What is claimed is:

l. A clear, stable liquid detergent consisting essentially of awater-soluble paraffin sulfonate salt having from 10 to 20 carbon atomsin the molecule, a compatible water-soluble higher alkyl ether sulfatesalt in a ratio of paraffin sulfonate to ether sulfate of about 10:1 to1:1; and means for controlling the viscosity and clarity of said liquiddetergent; wherein the total content of said paraffin sulfonate andalkyl ether sulfate salts is about 10 percent to about 60 percent byweight in an aqueous medium, the means for controlling the viscosity andclarity constitutes from about 6 to 13 percent by weight of the liquiddetergent composition and comprises a mixture of urea and a loweralkanol in a ratio of 1:1.5 to 1:3; said alkyl ether sulfate beingrepresented by the formula:

in which R is an alkyl group having 10 to 18 carbon atoms per molecule,n is a number from 1 to 10, and X is a cation; and the cation of thesulfonate and, said sulfate being selected from the group consisting ofalkali metals, alkaline earth metals, ammonium, and lower amines.

2. A detergent as set forth in claim 1 in which said paraffin sulfonateis a mixture of compounds having about 13 to 18 carbon atoms permolecule.

3. A detergent as set forth in claim 1 in which R is an alkyl grouphaving between 12 and 14 carbon atoms per molecule and n is a numberfrom 3 to 6.

4. A detergent as set forth in claim 1 which also contains a nonionicfoam builder selected from the group consisting of compounds representedby the formula:

in which R is an alkyl group having 10 to 18 carbon atoms and n is anumber from O to 10, and monoand diethanolamides and isopropanolamidesof a C,,,-C fatty acid, said foam builder being present in amounts up toabout 10 percent by weight of the liquid detergent.

5. A detergent as set forth in claim 4 in which R is an alkyl grouphaving 10 to 18 carbon atoms, n in the formula for said nonionic foambuilder is a number from 6. A detergent as set forth in claim 4 in whichsaid nonionic foam builder is lauric-myristic monoethanolamide.

7. A detergent as set forth in claim 1 which contains 20 to 35 percentby weight of sodium C -C paraffin sulfonate; 6 to 15 percent by weightof ammonium C,,-C alkyl triethenoxy ether sulfate; 0 to 6 percent byweight of lauric myristic monoethanolamide; a viscosity and claritycontrol agent comprising 0.5 to 5 percent by weight of urea and ,2 to 10percent by weight of lower alkanol; and water.

8. A detergent as set forth in claim 7 in which said alkanol is ethylalcohol.

9. A detergent as set forth in claim 7 in which said means forcontrolling the viscosity and clarity further includes a lower alkylbenzene sulfonate hydrotrope.

2. A detergent as set forth in claim 1 in which said paraffin sulfonateis a mixture of compounds having about 13 to 18 carbon atoms permolecule.
 3. A detergent as set forth in claim 1 in which R is an alkylgroup having between 12 and 14 carbon atoms per molecule and n is anumber from 3 to
 6. 4. A detergent as set forth in claim 1 which alsocontains a nonionic foam builder selected from the group consisting ofcompounds represented by the formula: RO(C2H4O)nH in which R is an alkylgroup having 10 to 18 carbon atoms and n is a number from 0 to 10, andmono- and diethanolamides and isopropanolamides of a C10-C14 fatty acid,said foam builder being present in amounts up to about 10 percent byweight of the liquid detergent.
 5. A detergent as set forth in claim 4in which R is an alkyl group having 10 to 18 carbon atoms, n in theformula for said nonionic foam builder is a number from 3 to
 6. 6. Adetergent as set forth in claim 4 in which said nonionic foam builder islauric-myristic monoethanol-amide.
 7. A detergent as set forth in claim1 which contains 20 to 35 percent by weight of sodium C13-C18 paraffinsulfonate; 6 to 15 percent by weight of ammonium C12-C15 alkyltriethenoxy ether sulfate; 0 to 6 percent by weight of lauric myristicmonoethanolamide; a viscosity and clarity control agent comprising 0.5to 5 percent by weight of urea and 2 to 10 percent by weight of loweralkanol; and water.
 8. A detergent as set forth in claim 7 in which saidalkanol is ethyl alcohol.
 9. A detergent as set forth in claim 7 inwhich said means for controlling the viscosity and clarity furtherincludes a lower alkyl benzene sulfonate hydrotrope.